Bug while using Numpy with Python 3

Hi! I just tried to do "Weak Point" (Electronic Station). I tried to solve the task with Python 3 and Numpy (see attached file). When running it, I get the error:

TypeError: <class 'list' at 0x87e4c0> is wrong data type
Fail: weak_point([[7,2,7,2,8],[2,9,4,1,7],[3,8,6,2,4],[2,5,2,9,1],[6,6,5,4,5]])

There is no line mentioned. I guess, it is an error in Numpy. On my own Computer (Linux Mint 17.3, Python 3.4.3, Numpy 1.8.2), the script works without errors. The script also works here on the servers, when I use Python 2.7 instead of Python 3.6a

From: Unknown

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